Was the hint about the Admiral or whatever being named Iroh? It sounds like the voice of this character is by the same guy that did Zuko.

Yes, both. He is naked after Zuko's uncle and he has a voice almost identical to Zuko. The same voice actor that did Zuko's voice is playing this new Iroh. Some people think he's Zuko's grandson, and some think he's Azula's grandson. Apparently, Adulation became the Fire Lord, bur nobody knows if she's still alive or of that title has been handed down to someone else now. He seemed quite a bit younger than Tenzin, so I don't think he's Zuko or Azula's son.

The creators have confirmed that Iroh II is indeed Zuko's grandson. The web site confirms that Zuko is alive, but other than a statue in front of the train station we haven't seen anything on the show about him.